Articulated downspouts are known in which a portion of the downspout is released from an initial storage position to a rainwater dispersal position. The purpose of such a design is to provide a storage position in which there is sufficient ground clearance for the unobstructed passage of lawn maintenance equipment such as lawn mowers, and a dispersal position in which rainwater is directed away from the foundation of the building to which the downspout is connected.
Conventionally, manual and electric means have been employed for actuating the articulated downspout. Several methods have also been devised for releasing the hinged portion of the downspout in response to the accumulation of rainwater in the downspout itself. For example, U.S. Pat. No. 3,375,851 to Henry, issued Apr. 2, 1968, discloses a hinged downspout assembly in which the lower portion of the downspout is released when a counterbalance receptacle located therein fills with rainwater. A drawback to this design, however, is that release is accomplished by shifting the center of gravity of the hinged portion to a position outside the imaginary vertical plane defined by the hinge. This results in an actuation means which is overly sensitive, and may require some additional retaining means to prevent actuation by the wind.
U.S. Pat. No. 3,316,928 to Weakley, issued May 2, 1967, discloses a downspout attachment which is released from its rest position by the flow of water against a vane located in the horizontal lower section of the downspout. Because of the vane's positioning, only a small cross-section is exposed to the flow of water through the downspout. Thus, the articulation means may not be responsive in a light rainfall.